Delivery of the placenta

The third stage of labour starts when your baby is born and ends when your placenta is delivered. The placenta is the spongy organ that attaches to the inside of your uterus and provides oxygen and nutrients to your baby through the umbilical cord during pregnancy. Once your baby is born, the placenta also needs to be delivered, and your uterus needs to contract rapidly to shut off the blood vessels that have been supplying it. For the majority of mothers, this happens easily within 30-60 minutes but, for around 3% of women, the placenta will remain within the uterus. This is called a “retained placenta” and requires medical assistance.

You are at higher risk of a retained placenta if you have had:

• A previous caesarean or surgery within your uterus
• A history of infection within your uterus
• Fibroids
• A previous retained placenta
• A premature delivery

Most third stages only take 5-10 minutes to complete, but the longer it takes, the more likely you are to bleed significantly. Your midwife or doctor will look for signs such as a small gush of blood, a change in the size and shape of the uterus when gently rubbed through your belly, and the cord hanging from the vagina lengthening by a few inches. At this point, you may feel the need to push, and with this effort, the placenta passes into the vagina and out into a bowl or bedpan. The midwife will then inspect it to make sure there are no missing pieces that may be left inside. Without any intervention, this process is called a physiological third stage. The process can be helped along by breastfeeding and by ensuring your bladder is empty.

Most women in the UK choose to have an injection containing either oxytocin or a combination of oxytocin and ergometrine immediately after their baby is born in combination with a technique called Controlled Cord Traction (CCT). This is called “active management of the third stage”. Your midwife or doctor performs CCT by holding your uterus firmly in place from the outside (pressing on your lower belly) while steadily pulling the cord. This speeds up the third stage and has been shown to reduce your risk of heavy bleeding; whether you have this treatment is entirely your choice, but your doctors will recommend it if you are at higher risk of bleeding after delivery.

Your midwife will ask an obstetrician to see you if your placenta has not come out after 30 minutes if you had the injection, or 60 minutes if you did not. A doctor will also be requested if the umbilical cord snaps as it is pulled. The doctor will ask your permission to examine you vaginally; this can be uncomfortable if you did not choose to have an epidural, but you should be offered gas and air if you wish. Sometimes a doctor will be able to grasp the placenta more firmly during this examination and help you deliver the placenta in the same place you delivered your baby. There is some evidence that injecting the cord with an oxytocin solution can help the placenta to detach, and some hospitals will offer this. However, if your placenta is still within the upper part of your uterus, your doctor will recommend a transfer to the operating theatre for a procedure called a manual removal of placenta.

How necessary is a manual removal of placenta?

While serious harm from a retained placenta is extremely rare in developed countries like the UK, this is due to the prompt treatment available. In less developed countries without access to the facilities to perform a manual removal of placenta, it is considered a dangerous complication. In some studies, nearly 1 in 10 women have died as a result, usually due to bleeding. As there are no reliable alternative treatments for a retained placenta, manual removal is a necessity for safe obstetric care.

What happens next?

Your doctor will explain the procedure and give you the opportunity to ask questions, before asking you to sign a consent form to confirm your agreement. They will also ask your permission to give you a blood transfusion in an emergency situation, because of the risk of heavy bleeding associated with a retained placenta. The procedure itself only takes around 5-10 minutes, but including time for anaesthetic and any perineal repair needed, you’re likely to be in theatre for around 30 minutes. Most often your partner and baby are not brought into the theatre; if you do not have a birthing partner, the midwives will care for your baby during this time.

This procedure first involves making the lower half of your body numb with an anaesthetic (either a spinal injection or, if you have one, a “top-up” of your epidural). Your legs will then be raised in supports and the doctor will perform another vaginal examination. If your placenta is simply being held by the cervix, it may be quick and easy to remove it. If it is still attached, the doctor will carefully insert their hand into the uterus and separate the placenta before removing it. During this process, you will be given antibiotics and may be given a range of medications to contract the uterus and stop or prevent further bleeding. Some of these can make you feel very sick, but this only lasts for a few minutes and the anaesthetist will give you some anti-sickness medication to help.

When this procedure is finished, the doctor will check for any tears that occurred during your birth and repair them if necessary. Finally, they will put a catheter in your bladder as you will not be able to feel when you need the toilet or get up to go for around 4-6 hours.

In rare circumstances, your placenta is abnormally stuck to the inside of the uterus and is very difficult to remove. This results in a high risk of heavy bleeding, and a senior obstetrician will be involved in your care. Once your placenta is removed, it is possible that your womb will still not contract adequately and you will continue to bleed. This rare situation, known as postpartum haemorrhage, can be treated, although be assured that the majority of women who need a manual removal of placenta require no further treatment.

Whether you have a physiological or active third stage, or whether your placenta is delivered vaginally, by manual removal or during caesarean, it is important that your placenta is checked to confirm it is complete. During a caesarean or manual removal, the doctor can also check the inside of your uterus directly to ensure no pieces of placenta remain. Retained placental tissue (also called a partially retained placenta) will cause bleeding and infection in the days and weeks after delivery. If your bleeding seems heavier than expected after birth or smells offensive, or if you start to feel unwell, contact your midwife, GP or Maternity Assessment Centre. They will perform a swab test to check for infection and are likely to start antibiotics. If it persists, you may need an ultrasound scan, and if this shows some placental tissue inside the womb, you will need a short operation to have this removed.

Main Points

• The placenta is the spongy organ that attaches to the inside of your uterus and provides oxygen and nutrients to your baby through the umbilical cord during pregnancy. This is delivered after your baby is born in what is known as the third stage of labour.
• Most women will deliver the placenta within 30-60 minutes after their baby is born, but if it remains in the uterus after this time, it is called a retained placenta.
• Risk factors that increase the likelihood of having a retained placenta include a previous caesarean, fibroids, a history of infection within your uterus, or a premature delivery.
• If there is no intervention during the third stage, this is known as a physiological third stage. If an injection using oxytocin is used, in combination with a technique known as Controlled Cord Traction, is known as active management of the third stage.
• The longer the third stage of labour takes, the more likely you are to bleed significantly.
• If you’ve not delivered the placenta after 30 minutes (if you’ve had an oxytocin injection) or an hour (if you haven’t), a doctor will be called to examine you. If the placenta is still in the upper part of the uterus, your doctor will recommend a transfer into an operating theatre for a procedure called a manual removal of the placenta.
• Manual removal is a necessity for safe obstetric care. Severe complications from a retained placenta are extremely rare in developed countries due to the prompt treatment available. However, in countries that lack the facilities to perform a manual removal, a retained placenta is very dangerous and can be fatal to the mother.
• Before the manual removal of the placenta, your doctor will ask you to sign a consent form and also ask for your permission to perform an emergency blood transfusion because there is a risk of heavy bleeding.
• During the procedure, the lower half of your body is made numb with anaesthetic, and the doctor will carefully insert their hand into the uterus to separate the placenta.
• The procedure, along with the administration of anaesthetic and repair of any perineal tears if required, should take around 30 minutes.
• Requiring manual removal of the placenta will mean that you’ll have a short time of separation from your baby and birth partner and a longer stay in the hospital. However, you may be able to breastfeed your baby before going into the operating theatre.
• Once your placenta is removed, it is possible that your womb will still not contract adequately and you will continue to bleed (postpartum haemorrhage). You will be treated for this.

References

Best Practice in Labour and Delivery. Cambridge University Press 2010
McDonald S. Management of the Third Stage of Labor. Journal of Midwifery & Women’s Health 2015 May-Jun;52(3):254-61
Carroll G, Bergel E. The Cochrane Library, Issue 4. Oxford: Update Software; 2000. Umbilical vein injection for management of retained placenta (Cochrane Review)
Weeks AD. The Retained Placenta, African Health Sciences 2001 Aug; 1(1): 36–41
Intrapartum care: care of healthy women and their babies during childbirth; NICE Clinical Guideline 2014